Field of the Invention
The disclosure relates to touch panel display technology, and in particular to a light shielding/decorative film for a touch sensor device.
Description of the Related Art
A touch sensor device is typically integrated with a flat panel display device, such as a liquid crystal display (LCD), an active matrix organic light-emitting display (AMOLED) or the like, to form a touch panel display. Touch panel displays are typically used in electronic devices, such as portable personal computers, personal digital assistants (PDAs), electronic books, projectors, mobile phones, and the like. The touch panel display is capable of conducting input functions by a finger, a stylus, a pen, or the like and therefore has gained an increasing amount of attention and popularity.
Generally, a shielding layer (e.g., a black matrix (BM) layer) is typically disposed in the peripheral region (i.e., a non-sensing region or a fan-out region) of a touch sensor device for light shielding or decoration. Currently, conventional black or white photoresist materials are used as the shielding layer. Moreover, the shielding layer are typically formed by a wet process (e.g., a screen printing or spin coating process), such that the shielding layer has a sufficient thickness (e.g., more than 1 μm) which is capable of providing a good light shielding effect. A step height, however, may be formed between the fan-out region and the sensing region due to the thick shielding layer, resulting in a mura defect between the fan-out region and the sensing region after depositing a transparent conductive layer for formation of sensing electrodes in subsequent processes, which reduces the display quality.
Accordingly, there exists a need in the art for development of a novel light shielding/decorative film structure, capable of mitigating or eliminating the aforementioned problems.